I don't see why the scene description language and the media types
of inlined data aren't completely orthogonal -a binding might have to be
described, as Tony has proposed for sound, but exactly what data type
that sound is doesn't need to be declared anywhere. HTTP will handle
the negotiation needed for media type incapabilities (i.e. the browser
says "hey, I can handle audio/mulaw, audio/mpeg, and audio/midi" and the
server goes "great! for this object I'll give you the MIDI version...").
Think orthogonally....
Brian